Just my 2 cents, but I don't think Devecchio was ever dirty. Based upon what I have read, the facts include:
1. Linda Shiro Scarpa lied through her teeth. Her testimony in court was proven to be a fabrication based upon tape recordings she made with Capeci when a book deal was being considered. In my opinion, she should have been charged with perjury.
2. The allegations against Devecchio were raised by a zealous, insubordinate agent who was on the Columbo task team who reported to Devecchio. This guy was later relocated out of NYC and every senior agent that has publicly commented on the allegations, claim this guy was trouble.
3. Devecchio has been supported by every single one of his superiors in the NYC office at the time. Kollstrum and others have consistently stated publicly the claims were not substantiated. These are honest cops, and if there was a shred of truth, they would have gone after Devecchio with the same vigor they went after LCN.
4. There is evidence the Columbos actually came up with the strategy to discredit Devecchio. Several of the cases against Columbo guys fell apart or were not prosecuted because of the allegations.
Draw you on conclusions after you have done the research. For me, the facts were very compelling that Devecchio was clean.
Deal with the devil makes a pretty convincing argument he was dirty, or at the very least, completely incompetent. But he was just as much of a liar as shiro was, if not more so. Everything from lying in court about getting Scarpa off jam after jam, to special treatment and cash perks. There are too many things that don't add up, such as Jr getting out the day befor they came to bust him? Or Scarpa getting a hold of the individual in federal custody in Kansas. There is countless other examples. On top of it, he should be a felon for selling firearms illegally, and booted out of the FBI. But Rudy Giuliani saved his ass. Im not 100% sure he's guilty. But pretty sure, otherwise Greg scarpa was the luckiest guy in the history of the world, and got more coincidencial breaks than any guy in history.
At the very least, we know that Lin DeVecchio was a dishonest liar, and he was willing to break the law (he only got off on the gun charge because of friends in high places).
